The invention relates to a method and device for classifying the driving style of the driver in a motor vehicle.
DE 44 01 416 C2 discloses a method for gradual driving style classification between steady and dynamic driving styles, in which during driving measured variables indicative of driving style are determined, and driving-style classification figures are calculated from the measured variables with the aid of a family of characteristics. These driving-style classification figures serve as a measure of whether a steady or a dynamic driving style is desired. Based on this claccification, parameters influencing the vehicle handling which are used to set the functioning of specific components of the vehicle, for example the antilock braking system, are calculated as a function of the driving-style classification figures and stored in a regulation and control unit.
In order to obtain a reliable classification and adaptation of the regulation and control unit to the respective driving style, the driving style is classified separately with regard to the acceleration behaviour, the braking behaviour and the steering behaviour. This approach takes account of the fact that the driving style can be characterized more precisely and aptly using a plurality of classification figures than using only one classification figure, the result of this being to reduce the risk of erroneous decisions by the system.
Moreover, driver identification devices are known, for example from DE 42 15 406 A1, by means of which a driver can be classified continuously in accordance with his driving style from economic to sporty/performance-orientated, and the vehicle can be set in accordance with the classification.
The invention is based on the problem of improving the handling of a motor vehicle with the aid of a driver classification.
According to the novel method contemplated by the present invention for solving this problem the first step is to determine driving-style classification figures for a plurality of different driver reaction stages. These driving-style classification figures grouped according to reaction stages are transmitted to a regulation and control unit of the vehicle and stored there.
After each start of the motor vehicle, indicators are determined which automatically permit an identification and/or classification of the current driver by measuring classified parameters and operating or state variables. After the current driver has been identified and/or classified with the aid of these measured indicators, the driving-style classification figures corresponding to this driver and stored in the regulation and control unit are activated.
This mode of procedure has, for one thing, the advantage that each time driving is started a set of driving-style classification figures which best describes the respective driver is activated, and the vehicle can be set with reference to the person with each start. By activating the corresponding set of driving-style classification figures, it is possible for reaction deficits, for example excessively slow reaction or excessively hesitant braking, to be compensated by the regulation and control unit, and this enhances driving safety. Long learning phases in which the vehicle normally has a neutral basic behaviour as long as the regulation and control unit has not yet adapted to the respective driver are eliminated or minimized.
In accordance with an advantageous development, a coarse classification is undertaken into three reaction stages which correspond to an average driver, a driver with slow reactions and a quickly-reacting driver. Starting from this coarse classification, the driving-style classification figures are expediently continuously adapted during ongoing driving in the vehicle, in order to take account of particular situations such as night driving, driving in rain or snow, or different daily states of a driver, for example caused by overtiredness. The classification figures, and consequently also the vehicle handling, are adapted in the vehicle to the situation with the aid of this fine classification.
The classification of a driver is performed on the basis of typical driver reactions. It is possible to determine the variation and/or the change in state variables, for example the pressure build-up in the hydraulics of the brake system or the steering system, or else, accelerations/retardations of the vehicle. These state variables serve as an indicator for classifying the driver into an appropriate reaction type. This mode of procedure has the advantage that no further parameters are required to identify the driver. In the case of a coarse classification into three reaction stages, the driver is grouped into that reaction stage which best reflects his ability to react.
It can, however, also be expedient, if appropriate, to store person-specific classification figures for one or a plurality of drivers individually in the regulation and control unit of the vehicle, and to activate these person-specific classification figures after starting driving by identifying the current driver, as a result of which a vehicle used by a plurality of persons can be optimally set to the respective driver directly after starting. The determination of person-specific classification figures can be performed with the aid of selected test drives in the vehicle or by means of driving simulators. Typical indicators which can be used to identify the current driver are, for example, the seating position set by the driver, or the driver weight acting on the driver""s seat.